chapter 14 pt 2 Flashcards
Fermentation
Anaerobic degradation of glucose to obtain energy conserved as ATP
In glycolysis the 1st phase (1st five steps) are called the ________________ phase
preparatory
In the first 3 steps of glycolysis ATP is the _______________ group donor
Phosphoryl
All sugars in glycolysis are _____ isomers
D
The 2nd phase (last 5 steps) is known as the ___________ phase
Payoff phase
What are the 3 types of chemical transformations that occur in glycolysis?
- Degradation of the carbon skeleton on glucose to make pyruvate
- Phosphorylation of ADP to ATP by compounds with high phosphoryl group transfer potential
- Transfer of a hydride ion to NAD+ forming NADH
One of the routes for pyruvate is the reduction to ____________ via lactic acid fermentation
Lactate
When we work out our contracting skeletal muscle must function in anaerobic conditions, NADH can’t be re-oxidized to NAD+ but NAD+ is needed for further oxidation of pyruvate in glycolysis so under anaerobic conditions pyruvate is reduced to lactate to accept electrons from NADH to regenerate the ________ needed for glycolysis
NAD+
Also under ____________ conditions pyruvate can be converted to ethanol & CO2 by ethanol fermentation
anaerobic
The conversion of glucose to pyruvate is ____________
Exergonic
The formation of ATP from ADP & Pi in glycolysis is ____________
Endergonic
The preparatory phase of glycolysis requires ________
ATP
_______ shields the negative charges of the phosphoryl group in ATP making the terminal phosphorus atom an easier target for nucleophilic attack
Mg2+
Glucose 6 phosphate is an _________
Aldose
The aldolase cleavage reaction in step 4 cleaves where?
By the alpha & beta carbon position
Why does glucose 6 phosphates convert into fructose 6 phosphate?
Because fructose 6 phosphate is energetically more favorable since when its cleaved it forms 2 3 carbon molecules
Fructose 6 phosphate is a __________
Ketose
Bisphosphates
Compounds that contain two phosphate (or phosphoryl groups) attached at different positions
The 3rd step in glycolysis is the _____________ step
First committed step
Glyceraldehyde 3-phosphate is a _______
Aldose
Dihydroxyacetone phosphate is a _______
Ketose
In the aldose cleavage of molecules one of the products is reduced (gains an H) & the other is oxidized so its OH turns into ______
C=O
The formation of glucose 6 phosphates to fructose 6 phosphate is needed because when fructose 6 phosphate turns into fructose ,6 bisphosphate it cleaves to form 2 3 carbon molecules which is __________ more favorable
energetically
The payoff phase of glycolysis yields ________ & ________
ATP & NADH
One molecule of glucose yields 2 molecules of ________________ for the payoff phase (both follow the same pathway)
glyceraldehyde 3 phosphate
Even though the reaction of dihydroxyacetone phosphate to form glyceraldehyde 3-phosphate is unfavorable it continues to occur rapidly because once glyceraldehyde 3 phosphate is made from dihydroxyacetone phosphate is instantly _______________ to keep the reaction occurring
Removed
The 6th step of glycolysis is the 1st ___________ conserving reaction of glycolysis
Energy
Substrate level phosphorylation
The formation of ATP by phosphoryl group transfer from a substrate such as 1,3-BPG reacting with ADP to form 3-phosphoglycerate & ATP
Glycolysis would stop if the NADH formed in step 6 wasn’t continuously ____________
Reoxidized to NAD+
In step 6 the formation of 1,3 BP6 can be thought of as 2 steps where the 2 steps are linked by the formation of an energy-rich ______________________ in the active site if glyceraldehyde 3 phosphate dehydrogenase to decrease the activation energy to make the reaction more favorable
Thioester intermediate
Step 7 is the 1st production of _____
ATP
Rapidly growing tumors obtain ATP by metabolizing glucose to lactate even in the presence of oxygen, a process termed aerobic glycolysis, what is this effect called?
Warburg effect
______________ glycolysis generates lactate acid, which acidifies the environment & may allow further tumor growth
Aerobic
Because tumors can grow faster than blood vessels, ____________ glycolysis alow growth in the absence of oxygen
Aerobic
Glycolysis mainly takes place in the _______
Cell
Gluconeogenesis mainly takes place in the _________
Liver
Gluconeogenesis is used to make ___________
“new glucose”
The enzyme ___________________ is located in the mitochondria
Pyruvate Carboxylase
___________ is required for Gluceonegensis
NADH, Gluceonegensis whole purpose is to make NADH
The __________ reaction of gluconeogenesis is oxaloacetate reacting with PEP carboxyase to form PEP (phosphoenolpyruvate)
2nd bypass
The _______________ reaction in gluconeogenesis is pyruvate reacting with pyruvate carboxylase to form oxaloacetate
1st bypass
_________ is produced by active skeletal muscle cells that undergo fermentation, it then moves into live cells & its transformed into pyruvate by lactate dehydrogenase
Lactate
_________ is produced from the breakdown of triglycerides in adipose tissue, it then enters the blood streams & travels to the hepatocytes where it converts into dihydroxyacetone phosphate (DHAP)
Glycerol
___________ are obtained from the hydrolysis of protein in our food, under starvation condition we can obtain amino acids from the breakdown of protein in our skeletal muscle tissue, some amino acids are converted into pyruvate while other are transformed into DHAP molecules to make glucose
Amino acids
Glycolysis
A process by which cells can extract a limited amount of energy from glucose
Fermentation
A process by which cells can continue using
glycolysis to extract energy in anaerobic conditions
Gluconeogenesis
A process by which cells can use a variety of
metabolites for the synthesis of glucose
The difference between glycolysis and gluconeogenesis is what?
- How they are both made thermodynamically favorable
- How they are differentially regulated to avoid a futile cycle
The pentose phosphate pathway
A process by which cells can
generate pentose phosphates and NADPH. The pentose phosphates can be regenerated into glucose-6-phosphate,
which requires no ATP.
Brain, nervous system, and red blood cells generate ATP ONLY from _________
glucose
